Shoe sewing machine



M y 1951 o. R. HAAS 2,551,599

SHOE SEWING MACHINE Filed Dec. 50, 1948 5/ Z6 3 fig 4 Inventor Patented May 8, 1951 SHOE SEWING MACHINE Otto it. Haas, Wenham, Mass,., assignor to United ShoeMachinery Corporation, Flemington, N. 3., a corporationof New Jersey Application December 30, 1948, Serial No. 68,120

3 Claims. (01. 112-48) The present invention relates to curved needle shoe sewing machines, and more particularly to improvements in work .feeding mechanisms for lockstitch outsole sewing machines of the type disclosed in United States Letters Patent No. 2,328,011, granted August 31, 1943 on application of Otto R. Haas.

In the machine of the prior patent above noted, the work is fed by a curved work penetrating instrument while engaging the work, the instrument being moved in the line of feed and then disengaged from the work. In the patent this instrument is an awl. To actuate the awl, it is mounted on an oscillating segment, the hub of which is grooved and is slidingly and rotatably mounted on the reduced right end of a stud. To move the awl segment in the line of feed the groove in the segment is engaged by the forked upper end of a feed lever fulcrumed on the machine frame, the lower end of the lever being actu- 1 ated by a cam on the main sewing shaft.

In the machine of the patent, the forked upper end of the feed lever has circular groove engaging enlargements, the diameters of which are approximately equal to the width of the groove. It frequently is difficult to provide or maintain accurately fitting surfaces between the up er end of the feed lever and the inner sides of the groove in the awl segment hub. After considerable wear of the parts, there is a likelihood that lost motion will develop between the enlargement and the hub of the segment and, accordingly, it is necessary to replace the entire feed lever with one having its upper end somewhat larger than the old one and often times a new awl segment is required.

Accordingly, the present invention ha for its object to provide a feeding mechanism for a shoe sewing machine of the type referred to in which the surfaces of the feed lever and the groove in the hub of the awl segment may readily be ad- 1 justed to take up wear or improper fit from manufacturing inequalities without replacing the parts. To this end in the machine of the invention, the awl or other work penetrating instrument operated by the segment having a grooved the machine. operator to force the machine to take long able plate and the feed lever is accomplished by a suitably arranged shim clamped between the plate and the feed lever.

This and other features of the invention as hereinafter described and claimed will be apparent from the following .detail specification taken in connection with the accompanying drawings, in which Fig. .1 is a fragmentary view in frontelevation of a portion of an outsole shoe sewing machine including those parts embodying the features of the present invention;

Fig. 2 is a view in right side elevation 10f the machine including the shuttle, needle, awl segment and actuating lever, the latter two of which are shown in Fig l;

Fig 3 is a sectional view taken alon the line III-III of Fig. .2; and

Fig. 4 is a detail view of an adjusting shim ;employed in the lever of Figs. 1 and 2.

In the machine disclosed in the .Haas patent above referred to, .if lost motion is present between the awl segment and the feed lever which actuates it irregularities are certain to result in the lengths of the successive stitches inserted by For instance, it is possible for the stitches or to hold back the work so that much shorter stitches are inserted. Furthermore, if,.no special effort is exerted either to lengthen or shorten the stitches one stitch may be long immediately followed by a short stitch so that an unsightly looking seam will be formed.

As in the machine of the patent, the present machine is a lockstitch outsole shoesewing machine having a curved work penetratin hook needle 10, a curved work-feeding awl l2, a shuttle l4 and other stitch forming and Work clamping devices. The work feeding awl is clamped ior oscillation with a segment [6 having gear teeth meshing with similar teeth on an actuating arm 18. The segment lthas a grooved hub 20 slidably and rotatably mounted on a fixed stud 22 secured at its left end in the machine frame .and having its right end mounted in a strap 2'4 bolted to a bracket .26 which is secured to the frame of the machine. The segment is reciprocated in the line of feed to impart a feeding movement to the awl while in engagement with the work We feed lever 28 fulcrumed on a pin 38 secured in the bracket 26 by a .drawbolt v32 (see Fig. 3,). The

pin 36 has its central "surface eccentric to its ends to enable suitable alining adjustments to be made relatively to the needle. The drawbolt 32 passes through the strap 24 and, together with a screw 34, maintains the strap and eccentric pin in place on the bracket 26.

The feed lever of the patented machine at its upper end is forked and provided with circular enlargements, the diameters of which are made to fit the spacing between the sides, indicated at 36, of the groove in the segment within close tolerances. The forked end of the feed lever embraces the hub of the segment to cause the enlargements to impart a thrust on both sides of the segment hub. During movement of the lever, a small extent only of the arcuate surfaces on the circular enlargements engage the inner surfaces 36 of the groove so that after the machine has been operated for some time these arcuate surfaces which are formed diametrically opposite to each other on the circular enlargements become worn, leaving slight free spaces between them and the groove surfaces. These free spaces in the groove are a troublesome source of lost motion between the parts. The feed lever 28 being actuated at its lower end by a ball-shaped head of a pin 38 engaging a socket in an actuating link 46, accordingly moves within the free space of the groove a distance equal to the lost motion. Consequently, there can be no assurance that a uniform feeding movement will be imparted through the awl to the work.

To avoid inaccurate feeding movements of the work by the awl and to reduce lost motion between the circular enlargements at the upper end of the fed lever and the sides 36 of the groove in the hub of the awl segment, the forked upper end of the illustrative feed lever has below its forked upper end a cut-away shank, and the upper end is formed with a semi-cylindrical arcuate shape to engage one surface 36 only of the groove at opposite sides of the needle segment hub. Clamped to the cut-away shank surface of the feed lever is a removable forked sector plate 42 having rounded portions at its upper end. The outer surface of the rounded portions are complemental to the arcuate surfaces on the feed lever and provided with said arcuate surfaces circular enlargements, similar to those in the patented construction, each of a diameter equal to the width of the groove in the awl segment. In case of inaccuracies in machining the parts or after usage or wear from other causes, the diameter of the enlargements therefore may readily be adjusted to take up lost motion in the machine of the present invention.

To adjust for lost motion the plate 12 has a perforated shank matching the shank of the feed lever. A pair of screws M pass through the perforations in the shank of the plate into threaded openings in the shank of the feed lever and between the two is disposed a forked shim 46 clamped in place by the screws. Thus, after lost motion occurs between the parts if no shim originally is clamped between the lever and plate, one of suitable thickness may be inserted or if a shim is already present between the parts a thicker one may be substituted in the usual way of machine adjustments by the use of shims.

To facilitate insertion and removal of the shim 46 the upper end of the shim shank is perforated at 43 for one of the screws and the lower end is slotted at 56. Accordingly, it is necessary only to loosen both screws 44 and remove the upper one only when replacing or inserting the shim.

The nature and scope of the invention having i been indicated and a particular embodiment having been described, what is claimed is:

1. A shoe sewing machine having work feeding mechanism comprising a curved work penetrating instrument, a segment having a grooved hub with which the work penetrating instrument oscillates, a fixed stud on which the segment is mounted for sliding movement, and a feed lever arranged with one end engaging the hub of the segment within its groove and formed with an arcuate surface to engage one side of the groove, in combination with means for reducing lost motion between the arcuate surface of the feed lever and said side of the groove, comprising a removable plate on the feed lever having a rounded portion, the outer surface of which is complemental to the arcuate surface 0f the feed lever and provides with said arcuate surface a circular enlargement of a diameter equal to the width of the groove in the segment hub.

2. A shoe sewing machine having work feeding mechanism comprising a curved work penetrating instrument, a segment having a grooved hub with which the work penetrating instrument oscillates, a fixed stud on which the segment is mounted for sliding movement, and feed a lever having on one arm a cut-away shank with a forked end embracing the hub of the segment within its groove and being formed with an arcuate surface to engage one side of the groove, in combination with means for reducing lost motion between the arcuate surface of the feed lever and said side of the groove, comprising a removable plate on the feed lever having a shank and a rounded portion, the outer surface of which is complemental to the arcuate surface of the feed lever, the shank of said plate being clamped to the shank of the feed lever.

3. A shoe sewing machine having work feeding mechanism comprising a curved work penetrating instrument, a segment having a grooved hub with which the work penetrating instrument oscillates, a fixed stud on which the segment is mounted for sliding movement, and a feed lever having on one arm a cut-away shank with a forked end embracing the hub of the segment within its groove and being formed with an arcuate surface to engage one side of thte groove, in combination with means for reducing lost motion between the arcuate surface of the feed lever and said side of the groove, comprising a removable plate on the feed lever having a shank and a rounded portion, the outer surface of which is complemental to the arcuate surface of the feed lever, the shank of said plate being clamped to the shank of the feed lever, and a forked shim provided with a shank which is clamped between the shanks of the feed lever and the removable plate.

OTTO R. HAAS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,207,332 Paxton July 9, 1940 2,328,011 Haas Aug. 31, 1943 2,438,491 Ashworth Mar. 30, 1948 2,444,062 Petrosino June 29, 1948 

